net/octeontx: fix port close

[ upstream commit 39e0717 ]

Segmentation fault has been observed while closing the ethernet
port. Reason for the segfault is, eth port close also shuts down
event device while other ethernet port is still using the event
device.

Fixes: da6c687 ("net/octeontx: add start and stop support")

Signed-off-by: Harman Kalra <hkalra@marvell.com>

drivers/net/octeontx/octeontx_ethdev.c

@@ -25,6 +25,11 @@
 #include "octeontx_rxtx.h"
 #include "octeontx_logs.h"
 
+/* Useful in stopping/closing event device if no of
+ * eth ports are using it.
+ */
+uint16_t evdev_refcnt;
+
 struct evdev_priv_data {
 	OFFLOAD_FLAGS; /*Sequence should not be changed */
 } __rte_cache_aligned;
@@ -490,7 +495,11 @@ octeontx_dev_close(struct rte_eth_dev *dev)
 	if (rte_eal_process_type() != RTE_PROC_PRIMARY)
 		return 0;
 
-	rte_event_dev_close(nic->evdev);
+	/* Stopping/closing event device once all eth ports are closed. */
+	if (__atomic_sub_fetch(&evdev_refcnt, 1, __ATOMIC_ACQUIRE) == 0) {
+		rte_event_dev_stop(nic->evdev);
+		rte_event_dev_close(nic->evdev);
+	}
 
 	octeontx_dev_flow_ctrl_fini(dev);
 
@@ -681,8 +690,6 @@ octeontx_dev_stop(struct rte_eth_dev *dev)
 
 	PMD_INIT_FUNC_TRACE();
 
-	rte_event_dev_stop(nic->evdev);
-
 	ret = octeontx_port_stop(nic);
 	if (ret < 0) {
 		octeontx_log_err("failed to req stop port %d res=%d",
@@ -1346,6 +1353,7 @@ octeontx_create(struct rte_vdev_device *dev, int port, uint8_t evdev,
 	nic->pko_vfid = pko_vfid;
 	nic->port_id = port;
 	nic->evdev = evdev;
+	__atomic_add_fetch(&evdev_refcnt, 1, __ATOMIC_ACQUIRE);
 
 	res = octeontx_port_open(nic);
 	if (res < 0)
@@ -1595,6 +1603,7 @@ octeontx_probe(struct rte_vdev_device *dev)
 		}
 	}
 
+	__atomic_store_n(&evdev_refcnt, 0, __ATOMIC_RELEASE);
 	/*
 	 * Do 1:1 links for ports & queues. All queues would be mapped to
 	 * one port. If there are more ports than queues, then some ports